Witnesses saw the top ripped off a double-decker bus near Russell Square close to King's Cross train terminal, and three more apparently coordinated explosions caused carnage on packed subway trains as Londoners made their way to work.
Hear the latest news from London plus a big-picture analysis from some of the world's top terrorism experts.
Rob Simon, defense and national security correspondent for the BBC
Rohan Gunaratna, head of terrorism research at the Institute of Defense and Strategic Studies.;
Louise Richardson, expert on international security and terrorist movements, author of "Five Degrees of Separatoin: Terrorists and Their Sponsors.";
Steve Simon, senior analyst at the RAND Corporation, author of "The Age of Sacred Terror: Radical Islam's War Against America." His forthcoming book is "The Next Attack.";
James Goddard, lives in the West London neighborhood.
Richard Heffernan, professor of government at the Open University of London.
This program aired on July 7, 2005.